A surgeon put his head on a desk and said "oh God" after learning that the wrong kidney had been removed from a patient who later died, a jury had been told.

Korean War veteran Graham Reeves, 70, died five weeks after the bungled operation at Llanelli's Prince Philip Hospital, during which his healthy left kidney removed during surgery instead of the right one which was diseased.

Consultant urologist John Gethin Roberts, 60, and registrar Mahesh Goel, 40, from Burnley, Lancashire, are on trial for manslaughter at Cardiff Crown Court, but both deny the charge.

Graham Reeves: victim of a "fateful chain of events."

The court heard that Mr Roberts, of Ty Coch in Swansea - responsible for overseeing the kidney removal - later performed a second operation on the patient despite being told not to by Carmarthenshire NHS Trust's director.

Senior nurse Mary Isaac told the trial on Wednesday about the events after the discovery of the mistake on 24 January, 2000.

"I went to see Mr Roberts and we went to my office. He was obviously distressed," she said.

"I asked him what he had done since and who he had informed. He told me he had rung the transplant centre and that the kidney was not suitable for transplantation.

The court heard that Mr Roberts was advised to begin "further clinical intervention" during a phone call to a fellow doctor.

"He had his head on the desk. He was distressed and said something like: 'Oh God'," Mrs Isaac said.

Second operation

The nurse then explained that during a subsequent conversation with Dr Peter Thomas - the NHS Trust Director - Mr Roberts was told not to perform any more surgery on Mr Reeves.

But, the jury was told that later that afternoon, Mr Roberts did perform another procedure on Mr Reeves, inserting a tube into the remaining kidney.

Prosecuting, Leighton Davies QC claimed that second operation must have subjected the patient to "substantial stress" and he later developed cardiac and breathing problems.

The jury had already been told that Mr Goel did not check the patient's notes properly before the operation and so began a "fateful chain of events".

Mahesh Goel denies the manslaughter charge

Retired pipe lagger and bachelor Mr Reeves underwent the operation because he was suffering a stone in his right kidney.

Two hours after that operation, the blunder came to light when the patient was unable to pass urine.

He was transferred to Morriston Hospital the following day where he underwent specialist dialysis.

But Mr Reeves went on to develop septicaemia - blood poisoning - and his condition deteriorated and his diseased kidney then had to be removed.

The trial continues.